Django Rest Framework threoy
rest_framework源码分析:
1.as_view()
2.父类的as_view() view = super(APIView, cls).as_view(**initkwargs)
3.view 方法中 return self.dispatch(request, *args, **kwargs)
4.dispatch
1.将原来的request进行分装成restframework
request = self.initialize_request(request, *args, **kwargs)
self.request = request
2.处理版本,认证,权限,访问频率
self.initial(request, *args, **kwargs)
1.处理版本信息
version, scheme = self.determine_version(request, *args, **kwargs),request.version, request.versioning_scheme = version, scheme
if self.versioning_class is None:return (None, None)没有版本控制类,不做版本控制
scheme = self.versioning_class()#如果有走版本控制类
return (scheme.determine_version(request, *args, **kwargs), scheme)
version = kwargs.get(self.version_param, self.default_version) 获取版本
if not self.is_allowed_version(version): 如果版本不存在或者不在允许范围内
2.处理认证信息
self.perform_authentication(request)
request.uer 进入带有装饰器@Propryty 下的uer方法
if not hasattr(self, '_user'): #判断是否没有认证
self._authenticate() #没有认证,进入_authenticate()认证
for authenticator in self.authenticators: #循环获取认证对象
authenticators=self.get_authenticators() #将认证对象封装到 authenticators
return [auth() for auth in self.authentication_classes] #列表循环实例化authentication_classes列表的类的对象
authentication_classes = api_settings.DEFAULT_AUTHENTICATION_CLASSES #默认使用setting的配置
#认证过了直接返回
return self._user
3.处理权限信息
self.check_permissions(request)
for permission in self.get_permissions(): 从permission_classes中/获取权限类,在执行对象的列表生成式
if not permission.has_permission(request, self): 执行每一个类的has_permission进行权限认证
permission_denied(self, request, message=None) #如果权限认证失败执行
def permission_denied(self, request, message=None):
"""
If request is not permitted, determine what kind of exception to raise.
"""
if request.authenticators and not request.successful_authenticator:
raise exceptions.NotAuthenticated('无权访问')
raise exceptions.PermissionDenied(detail=message)
4.处理访问频率限制
self.check_throttles(request)
for throttle in self.get_throttles(): 从throttle_classes=[MyThrottle,] 循环获取节流对象
if not throttle.allow_request(request, self): 执行对象的allow_request(request, self)方法,成功返回True
self.throttled(request, throttle.wait()) 访问频率限制执行throttled(request, throttle.wait())
def throttled(self,request,wait): 在APIView中
class InnerThrottled(exceptions.Throttled):
default_detail = '请求被限制.'
extra_detail_singular = 'Expected available in {wait} second.'
extra_detail_plural = '还需要再等待{wait}秒'
raise InnerThrottled(wait)
throttle.wait() 返回,剩余多少时间可以进行再访问
在自定制的频率限制类中实现:
def wait(self):父类已经实现
3.根据用户提交的方法反射请求方法
handler = getattr(self, request.method.lower(),)
4.将处理后的数据进行,序列化,路由,渲染等方式进行封装
self.response = self.finalize_response(request, response, *args, **kwargs)